河南省区域经济、金融空间结构变化对比分析     

彭宝玉  张敏  郭扬 《地域研究与开发》2012,31(5)

基于泰尔指数和GIS地图分析技术,对河南区域经济和区域金融空间结构变化做对比分析.结果表明:金融业的空间集聚度远大于一般产业,在强大的金融集聚经济作用下,区域经济发展与区域金融发展会表现出显著差异.2000年以来,河南省辖市市区经济实力相对下降,而金融集聚功能上升;县域经济显著发展,而金融发展普遍滞后,郑州市日益成为全省金融服务业的集聚地.金融空间流动带来现代城市的快速成长、功能彰显和激烈竞争,而此种努力的结果往往会抑制一些区域的金融发展,特别是县域和农村地区,需要统筹区域金融中心和乡村普惠金融建设.  相似文献   

都汶公路沿线泥石流危险性评价     

韩用顺  黄鹏  朱颖彦  孔亚平  胡凯衡  李龙伟 《山地学报》2012,(3):328-335

汶川地震诱发的次生泥石流灾害,已成为灾区防灾减灾工作的突出问题和灾后恢复重建的重要制约因素之一,泥石流危险性评价是泥石流灾害风险管理的核心基础技术。以都汶公路沿线的31条泥石流沟为研究对象,通过野外考察、遥感图像的解译、查阅相关文献资料等手段获取研究区泥石流沟的基础数据,通过选取地质、地形、气象、水文指标,并利用主成分分析法对关键因子进行筛选和灰色系统模型进行权重的确定,建立泥石流危险性评价模型,计算得到每条沟的泥石流危险度值。评价结果表明:公路沿线31条泥石流沟处于不同泥石流危险等级:极高危险占23%,高危险占35%,中度危险占13%,轻度危险占29%;其中红椿沟、肖家沟、烧房沟等沟属于泥石流极高危险沟道,高家沟、牛圈沟等属于高度危险沟道,公路选线须采取避让或充分的防治对策。  相似文献   

开垦对内蒙古温带草地土壤不同有机碳组分的影响(英文)   总被引：3，自引：2，他引：1  

齐玉春  董云社  彭琴  肖胜生  何亚婷  刘欣超  孙良杰  贾军强  杨智杰 《地理学报(英文版)》2012,22(2):315-328

Cultivation is one of the most important human activities affecting the grassland ecosystem besides grazing, but its impacts on soil total organic carbon (C), especially on the liable organic C fractions have not been fully understood yet. In this paper, the role of cropping in soil organic C pool of different fractions was investigated in a meadow steppe region in Inner Mongolia of China, and the relationships between different C fractions were also discussed. The results indicated that the concentrations of different C fractions at steppe and cultivated land all decreased progressively with soil depth. After the conversion from steppe to spring wheat field for 36 years, total organic carbon (TOC) concentration at the 0 to 100 cm soil depth has decreased by 12.3% to 28.2%, and TOC of the surface soil horizon, especially those of 0-30 cm decreased more significantly (p<0.01). The dissolved organic carbon (DOC) and microbial biomass carbon (MBC) at the depth of 0-40 cm were found to have decreased by 66.7% to 77.1% and 36.5% to 42.4%, respectively. In the S.baicalensis steppe, the ratios of soil DOC to TOC varied between 0.52% and 0.60%, and those in the spring wheat field were only in the range of 0.18%-0.20%. The microbial quotients (qMBs) in the spring wheat field, varying from 1.11% to 1.40%, were also lower than those in the S. baicalensis steppe, which were in the range of 1.50%-1.63%. The change of DOC was much more sensitive to cultivation disturbance. Soil TOC, DOC, and MBC were significantly positive correlated with each other in the S. baicalensis steppe, but in the spring wheat field, the correlativity between DOC and TOC and that between DOC and MBC did not reach the significance level of 0.05.  相似文献   

Impact of global warming on drought in China     

Xian Xue  Tao Wang  Jian Guo  YuanHe Yang  Fei Peng  LiChao Liu 《寒旱区科学》2012,4(3):0201-0210

Spatial and temporal change patterns of air temperature (T), precipitation (P), relative humidity (RH), lower vapor pressure (VP), potential evapotranspiration (PET) and drought situation of 690 meteorological stations for all of China were evaluated in this study to understand the effects of warming on regional drought and hydrological processes. Here, the drought extent is expressed by aridity index (AI), which is the ratio of precipitation and reference crop evapotranspiration (ET₀) calculated by FAO Penman-Monteith equation, taking into account air temperature, atmospheric humidity, solar radiation, and wind. Our results indicate that there are different patterns of climate change from 1961 to 2008 and from 1981 to 2008. Little precipitation change occurred in China and ET₀ decreased from 1961 to 2008. But, the warming trend has intensified and the area with significant increasing precipitation has reduced since the early 1980’s and ET₀ has increased in most areas of China from 1981 to 2008 and decreased from 1961 to 2008. The areas affected by drought have shifted from North China and Northeast China to East China and South China since 1981. It is speculated that the increasing warming intensity after 1981 possibly strengthened the power of potential evapotranspiration and resulted in drought in most areas of Northeast China, North China, eastern Southwest China, and especially in East China and South China.  相似文献   

Monitoring Mongolia Gobi dust transport using OMI data     

KeYi Chen  ZhiQiang Peng 《寒旱区科学》2012,4(5):0446-0451

The characteristics of long-distance dust transport from Asia to the United States over the Pacific Ocean are statistically analyzed using OMI AI (Ozone Monitoring Instrument Aerosol Index) data during 2005–2007. The results show that there is a high correlation of AI (the correlation coefficients are as high as 0.83 in March, 0.62 in April and 0.54 in May) between the Mongolia Gobi Desert and the west coast region of the United States (40°–50°N, 120°–130°W), indicating a strong source-receptor area relationship. Through calculating the lag correlation coefficient of the dust propagation time, we determined that the dust propagation time from the Mongolia Gobi Desert to the west coast of the United States is about 6–7 days at the 99% confidence level.  相似文献   

兰州市土壤一蔬菜系统典型重金属空间评价及健康风险分析          下载免费PDF全文

齐鹏  张仁陟  张伯尧  王晓娇 《干旱区地理》2012,35(1):162-170

通过田间试验和室内分析相结合,对兰州市蔬菜和土壤中重金属cd、Hg、Pb、As和cr的含量进行测定并评估经食入途径对人体的健康风险,同时运用改进的物元模型综合评价兰州市三县四区土壤重金属污染并进行分区。结果表明：（1）兰州市菜地土壤中Cd、Hg、Pb、As和cr的平均含量都高于背景值,存在明显的积累,但均低于《土壤环境...  相似文献   

沙丘不同部位土壤呼吸对人工降水的响应   总被引：4，自引：0，他引：4  

禹朴家  徐海量  王炜  张鹏  赵新风  龚君君 《中国沙漠》2012,32(2):437-441

 利用LI-8100土壤呼吸测量仪,对古尔班通古特沙漠南缘阜康北部地区沙丘不同部位（坡底、坡中、坡顶）的土壤呼吸速率进行了测量,探讨了沙丘不同部位土壤呼吸速率对降雨的响应,分析了土壤水分和土壤温度对土壤呼吸速率的影响。结果表明:①沙丘不同部位土壤呼吸速率的日变化呈“双峰曲线”,而增雨处理后,土壤呼吸速率的日变化曲线大部分转变为“单峰曲线”。②增雨处理增加了沙丘不同部位土壤呼吸速率的变化幅度、平均值和极差,推后了土壤呼吸速率最大值到来的时间。③土壤呼吸速率与土壤温度的相关性对降雨表现出积极的响应,降雨改变了土壤温度的日变化曲线类型,提高了土壤温度与土壤呼吸速率的相关系数。④非增雨处理时,沙丘坡底、坡中和坡顶的土壤呼吸速率与土壤水分的相关性系数均较高,而增雨处理后,土壤呼吸速率与土壤水分的相关系数有所下降,仅坡中的相关系数通过了α=0.01的显著性检验。  相似文献   

中国建设用地与区域社会经济发展关系的空间计量研究   总被引：3，自引：0，他引：3  

叶浩  张鹏  濮励杰 《地理科学》2012,(2):149-155

利用空间计量模型,对中国大陆地区的30个省、市、自治区2008年的建设用地面积与社会经济发展之间的关系进行了研究。研究表明:30个省、直辖市和自治区地区建设用地面积、GDP、总人口和城市化率都有显著的空间相关特征,一个区域社会经济的发展不仅会驱动自身区域建设用地的扩张,而且会带动邻近区域的建设用地的增长。传统上只从时间维度出发的研究思路,忽视空间维度的相关性和异质性,低估了区域社会经济发展对建设用地增长的作用,必须在普通面板线性回归模型中描述的基础上引入空间变量进行修正。计量模型检验表明,城市化水平对建设用地总规模的影响不甚显著。说明中国大部分省份的农村居民点用地的利用效率普遍偏低。因此,农村居民点用地的调整与优化已迫在眉睫,从长远看来,提高城市化水平,打破城乡二元化的土地制度,建立统一的土地市场,是缓解土地资源紧缺、提高土地利用效率的有效途径。  相似文献   

近60年洞庭湖泊形态与水沙过程的互动响应   总被引：2，自引：0，他引：2  

尹辉  杨波  蒋忠诚  曾发明  彭鹏  李景保 《地理研究》2012,31(3):471-483

以历史文献、图件及1951～2009年长系水沙等资料为依据,对比分析洞庭湖形态与水沙过程的互动响应,结果表明:由于湖泊形态与水沙过程存在着相互作用的关系,近60年间,水沙过程以多种形式改变湖泊形态特征值,如湖盆结构破碎、解体,水深变浅以及湖面﹑湖容依次减少1840km²及130×10⁸m³;同时湖泊形态特征值改变也引起水沙特性变异,在1951～2002年间湖盆蓄水量呈明显的增减波动,但同流量下汛期水位普遍抬高1.2～1.90m,西﹑南﹑东洞庭湖水位变幅依次增大1.61m、1.39m和1.35m,各主要水文站前5位最高洪水位排序的年份均出现在湖面积(容积)历史最低值,泥沙淤积率为70%以上;2003年6月三峡水库蓄水及"退田还湖"后,高、中水位下湖盆调蓄量有所减少,城陵矶丰、枯水位分别降低1.12m及0.35m,西湖区与东南湖区的泥沙输出比均呈增大趋势,泥沙淤积率减至35.9%。其互动响应机制,可概化为泥沙淤积循环→湖盆结构破碎、解体,湖面湖容缩小→水沙特性异变→改变湖泊形态→水沙特性变异的互动响应动态演进模式。  相似文献   

Observed Impact of the South Asian Summer Monsoon on the Local Meteorology in the Himalayas   总被引：1，自引：1，他引：0       下载免费PDF全文

ZHOU Libo  ZOU Han  MA Shupo  LI Peng 《Acta Meteorologica Sinica》2012,26(2):205-215

The South Asian summer monsoon(SASM) is the most important climate system in Asia.Using observational data from the HEST2006(Himalayan Exchange between the Surface and Troposphere 2006) campaign and large-scale grid data,this paper analyzed the SASM impact on local meteorological parameters including radiation,temperature,humidity,and wind in the Himalayas.The SASM experienced one active and one break period during the HEST2006 campaign.The local meteorological parameters exhibit great differences between the active period and the break period of the SASM.The radiation fluxes are greater in the break period than in the active period.The air temperature and specific humidity are lower,but soil temperature and wind speed are higher in the break period than in the active period.Further analysis indicates that the SASM greatly affects the meteorological features of the Himalayan region.  相似文献